cpu.h

一个简单的虚拟机和虚拟操作系统

/*
 * CPU.h
 * this file define the class CPU
 */
#pragma once
#include "all.h"
#include <memory>
using namespace std;

extern int mem[MEM_SIZE];

class CPU
{

friend class VM;

public:
	CPU();


/***********************************************
 * public interface
 */
public:
	//clear all the registers
	void Reset();

	//fetch instruction into the instruction registers from memory
	void FetchIns();

	//process current instruction 
	//which is stored in the instruction registers
	void DoOperation();


/***********************************************
 * handle the operations
 */
private:
	void Handle_LOAD(int r,int m);
	void Handle_STOR(int m,int r);
	void Handle_MOV(int r1,int r2);

	void Handle_ADD(int r1,int r2);
	void Handle_SUB(int r1,int r2);
	void Handle_MPY(int r1,int r2);
	void Handle_DIV(int r1,int r2);
	void Handle_INC(int r);
	void Handle_DEC(int r);
	void Handle_JMP(int m);
	void Handle_JPZ(int m,int r);

	void Handle_OPEN(int IO);
	void Handle_CLOSE(int IO);
	void Handle_IN(int r);
	void Handle_OUT(int r);
	

	void Handle_HALT();
/***********************************************
 * assert the register ID or memory 
 * adderss is valid
 */
private:
	void Assert_REG(int r);
	void Assert_DataADRS(int address);
	void Assert_InsADRS(int address);

private:
	int GetDirAddress(int address);

/***********************************************
 * all the registers
 */
private:
	//common registers
	int R[24];
	//program counter registers
	int PC;
	//instruction register
	int IR[3];
	//this register records the the head address of the process  
	int PAR;
	//this register records the length of the process instruction section
	int PILR;
	//this register records the length of the process data section
	int PDLR;
};